Wound coverings are, as is known, required for burns, extensive skin wounds or skin lesions, open soft tissue injuries, pressure sores (decubitus), leg ulcers (ulcera cruris), wound ruptures (wound dehiscences) and the like. Wounds of this type are subject to contamination by germs (including fungi) and may then become septic wounds, which are slow to heal and require a special wound covering and wound treatment.
For such applications there exist to date gauze compresses and compresses of other suitable materials, whereby organic materials, in particular pigskin or collagen web, or metal foils such as, in particular, aluminum foils are employed. Moreover, synthetic organic materials can be used in the form of foams, gels or films, mats and powders. These include adipose gauze, polyurethane foams and mats, coverings of polytetrafluoride or polyvinyl chloride, Teflon/polyurethane foils, silicone-based materials and liquid-absorbing powders (e.g. based on dextran). The presently known wound coverings made from such materials are usually applied to the wounds in the form of sheets or mats. Wound exudate may thereby occasionally be retained under the covering material which is used, and this may subsequently lead to a delay in healing of the wound. If bacterial invasion occurs, a festering infection results, even in some cases when the dressing is changed several times a day.
West German Auslegeschrift DE-AS No. 1,161,384 discloses a metallized, absorbent dressing material. This dressing material comprises a fine-pored, absorbent, felt-like, compacted fiber fleece which is provided with a fine metal coating on the fiber surfaces without impairing the web structure. Metallized dressing materials of this type do not convey any impetus to provide a layer of ceramic or glass in the sense of the present invention in order to achieve the advantages and effects described hereinafter.
Further, U.S. Pat. No. 3,842,830 discloses a material for the formation of a surgical dressing which consists of inert ceramic microparticles and a method for forming such a dressing in situ. These microparticles have a specific weight of over 1 and, in addition, are of a size in the range of mesh number 100 to 3000. This previously known surgical dressing is produced on the spot by applying the aforementioned ceramic microparticles directly onto the wet tissue surfaces in the area of the injury. The microparticles can be dusted like powder onto the wound. A connection by means of connecting members or a web is the opposite of this previously known formation of a surgical dressing in situ.
The principal requirement for such wound coverings is for permeability to oxygen and liquids (e.g. wound exudates and therapeutic solutions). Moreover, such coverings should be made tissue-compatible and should promote granulation, i.e. they should be biocompatible and also, if possible, bioactive. An additional requirement is for sufficient mechanical flexibility. The aforementioned requirements are not met in a satisfactory manner with the previously known materials since, as a rule, only individual requirements are satisfied, and not all requirements simultaneously.